Boot swabs : An Essential Tool for Ground Surface Sampling

The United States is the world’s largest poultry producer, with 17% of its production exported in 2022. [1] Americans are also the top consumers of chicken, averaging over 101 pounds per person annually, making it the most popular protein in the country. [2] Given these figures, stringent food safety standards are essential in the poultry industry to ensure a safe product for consumption, particularly in preventing Salmonella contamination.

For years, the Food Safety and Inspection Service (FSIS) has aimed to reduce Salmonella infections linked to poultry products. However, recent approaches have yet to achieve a satisfactory level of success.

Proposed Regulatory Framework by FSIS

This is why, in 2022, the Food Safety and Inspection Service (FSIS) proposed a regulatory framework aimed at significantly reducing illnesses caused by Salmonella in the poultry sector. This proposal is built on three key components:

1.  Salmonella testing in poultry flocks before entering processing facilities : This measure aims to encourage pre-harvest interventions that reduce Salmonella contamination levels upon arrival or lower the risk of specific serotypes entering the facility.
2.  Enhanced oversight of process control within facilities and FSIS verification : This component focuses on improving monitoring procedures by tracking multiple sampling locations and applying a statistical approach to process control.
3.  Implementation of a final product standard : This measure assesses whether certain levels or strains of Salmonella in raw poultry products pose a high risk to human health and should be classified as adulterants. FSIS is considering adopting one or more final product standards to ensure that poultry contaminated with high levels of Salmonella is not sold to consumers.

In April 2024, FSIS finalized its policy to protect consumers from Salmonella in raw breaded stuffed chicken products. Under this policy, Salmonella will be classified as an adulterant in these products when contamination exceeds a specific threshold of one colony-forming unit (CFU) per gram or more.

Designating Salmonella as an adulterant places pressure not only on processors, who will need to conduct food safety testing, but also on primary producers, who must ensure they supply healthy, bacteria-free chickens.

Boot swabs, an essential tool

Effective Salmonella detection depends on selecting the right sampling procedure and using a sensitive culture method. To support this, poultry producers can rely on boot swabs, or boot covers, a surface sampling tool designed to help monitor Salmonella prevalence, reduce contamination risks, and maintain flock health.

Worn over work boots, these swabs allow employees to collect floor samples effortlessly while performing other tasks, such as swabbing additional surfaces with wipes.

Taking Inspiration from European Regulations 

The use of boot swabs has been well established in Europe since 2003. European regulations require regular Salmonella monitoring in poultry farms, and boot swabs are a widely used method for this purpose. Their widespread adoption in Europe has significantly improved the detection and management of Salmonella, helping to reduce contamination rates and protect public health. Other countries, including the United States and Canada, could benefit from following Europe’s example by incorporating boot swabs more broadly into their biosecurity practices to strengthen Salmonella control.

Studies conducted in the United States have shown that results obtained using boot swabs are comparable to—or even superior to—those of traditional swab testing methods. [3] This is partly due to the fact that boot swabs are pre-moistened with a solution that enhances the detection of Salmonella in poultry house fecal matter.

The Benefits of Boot Swabs

In poultry farming, fecal matter is the primary sample matrix for Salmonella detection. For floor-raised poultry, boot swabs are the preferred method for fecal sampling. They can be used as part of routine flock inspections and easily sent to a laboratory for analysis.

Use of Boot Covers in the Poultry Industry

To illustrate how boot swabs are used in the poultry industry, let’s take broiler flocks as an example. At least two pairs of boot swabs should be used per sampling session, with each pair covering approximately 50% of the area. The swabs are placed over work boots, and the sample is collected by walking through the poultry house. Once the process is complete, the boot swabs are carefully removed to prevent dislodging adherent material. They are then placed in a bag or container, labeled, and sent to the laboratory for analysis. Boot swabs from a single broiler flock can be pooled into one composite sample.

Additionally, boot swabs offer numerous advantages:

• Ease of use: They are easily worn over work boots and do not require complex additional equipment.
• Representative sampling: By walking through different areas of the facility, workers can collect a more comprehensive picture of pathogen presence.
• Reduced cross-contamination risks: Since boot swabs are disposable, they minimize the risk of spreading contamination between different areas or farms, unlike reusable methods.
• Cost-effectiveness: They are more affordable than many other sampling techniques.

Boot swabs are therefore a practical, efficient, and cost-effective tool for ground sampling in poultry farms, contributing to flock health monitoring and reducing the risk of pathogen contamination, including Salmonella.

Conclusion

Combating Salmonella in the poultry industry requires rigorous and innovative measures, such as those proposed by the FSIS in 2022. Adopting proven techniques, like the widespread use of boot swabs in Europe, can play a key role in reducing infections. Their simplicity, effectiveness, and affordability make them a practical solution for enhancing Salmonella monitoring, ultimately contributing to food safety and public health.

Sources

[1]https://alabamafeedandgrain.com/wp-content/uploads/2024/04/Peterson-Latest-challenges-opportunities-in-the-broiler-industry-v2024-03-24.pdf

[2] Ibid.

[3] Gradel, K. O., Andersen, J., & Madsen, M. (2002). Comparisons of sampling procedures and time of sampling for the detection of Salmonella in danish infected chicken flocks raised in floor systems. Acta Veterinaria Scandinavica, 43(1), 21–30. https://doi.org/10.1186/1751-0147-43-21

https://www.hygiena.com/fr/news/tout-ce-que-vous-devez-savoir-sur-le-cadre-reglementaire-du-fsis-pour-la-volaille

https://www.fsis.usda.gov/inspection/inspection-programs/inspection-poultry-products/reducing-salmonella-poultry/proposed

https://www.usda.gov/media/press-releases/2024/04/26/usda-finalizes-policy-protect-consumers-salmonella-raw-breaded

Carrique-Mas, J. J., & Davies, R. H. (2008). Sampling and bacteriological detection of Salmonella in poultry and poultry premises: a review. In Rev. sci. tech. Off. int. Epiz (Vol. 27, Issue 3).